Move currentDisplayMode to the ViewState

vector/src/main/java/im/vector/riotx/features/home/HomeDetailFragment.kt

@@ -51,8 +51,6 @@ data class HomeDetailParams(
 ) : Parcelable
 
 
-private const val CURRENT_DISPLAY_MODE = "CURRENT_DISPLAY_MODE"
-
 private const val INDEX_CATCHUP = 0
 private const val INDEX_PEOPLE = 1
 private const val INDEX_ROOMS = 2
@@ -61,7 +59,6 @@ class HomeDetailFragment : VectorBaseFragment(), KeysBackupBanner.Delegate {
 
     private val params: HomeDetailParams by args()
     private val unreadCounterBadgeViews = arrayListOf<UnreadCounterBadgeView>()
-    private lateinit var currentDisplayMode: RoomListFragment.DisplayMode
 
     private val viewModel: HomeDetailViewModel by fragmentViewModel()
     private lateinit var navigationViewModel: HomeNavigationViewModel
@@ -80,15 +77,16 @@ class HomeDetailFragment : VectorBaseFragment(), KeysBackupBanner.Delegate {
 
     override fun onActivityCreated(savedInstanceState: Bundle?) {
         super.onActivityCreated(savedInstanceState)
-        currentDisplayMode = savedInstanceState?.getSerializable(CURRENT_DISPLAY_MODE) as? RoomListFragment.DisplayMode
-                             ?: RoomListFragment.DisplayMode.HOME
 
         navigationViewModel = ViewModelProviders.of(requireActivity()).get(HomeNavigationViewModel::class.java)
 
-        switchDisplayMode(currentDisplayMode)
         setupBottomNavigationView()
         setupToolbar()
         setupKeysBackupBanner()
+
+        viewModel.selectSubscribe(this, HomeDetailViewState::displayMode) { displayMode ->
+            switchDisplayMode(displayMode)
+        }
     }
 
     private fun setupKeysBackupBanner() {
@@ -126,11 +124,6 @@ class HomeDetailFragment : VectorBaseFragment(), KeysBackupBanner.Delegate {
     }
 
 
-    override fun onSaveInstanceState(outState: Bundle) {
-        outState.putSerializable(CURRENT_DISPLAY_MODE, currentDisplayMode)
-        super.onSaveInstanceState(outState)
-    }
-
     private fun setupToolbar() {
         val parentActivity = vectorBaseActivity
         if (parentActivity is ToolbarConfigurable) {
@@ -156,10 +149,7 @@ class HomeDetailFragment : VectorBaseFragment(), KeysBackupBanner.Delegate {
                 R.id.bottom_action_rooms  -> RoomListFragment.DisplayMode.ROOMS
                 else                      -> RoomListFragment.DisplayMode.HOME
             }
-            if (currentDisplayMode != displayMode) {
+            viewModel.switchDisplayMode(displayMode)
-                currentDisplayMode = displayMode
-                switchDisplayMode(displayMode)
-            }
             true
         }
 

vector/src/main/java/im/vector/riotx/features/home/HomeDetailViewModel.kt

@@ -24,10 +24,12 @@ import com.squareup.inject.assisted.AssistedInject
 import im.vector.matrix.android.api.session.Session
 import im.vector.matrix.rx.rx
 import im.vector.riotx.core.platform.VectorViewModel
+import im.vector.riotx.features.home.room.list.RoomListFragment
 import io.reactivex.schedulers.Schedulers
 
 /**
- * View model used to update the home bottom bar notification counts
+ * View model used to update the home bottom bar notification counts, observe the sync state and
+ * change the selected room list view
  */
 class HomeDetailViewModel @AssistedInject constructor(@Assisted initialState: HomeDetailViewState,
                                                       private val session: Session,
@@ -53,6 +55,14 @@ class HomeDetailViewModel @AssistedInject constructor(@Assisted initialState: Ho
         observeRoomSummaries()
     }
 
+    fun switchDisplayMode(displayMode: RoomListFragment.DisplayMode) = withState { state ->
+        if (state.displayMode != displayMode) {
+            setState {
+                copy(displayMode = displayMode)
+            }
+        }
+    }
+
     // PRIVATE METHODS *****************************************************************************
 
     private fun observeSyncState() {

vector/src/main/java/im/vector/riotx/features/home/HomeDetailViewState.kt

@@ -18,8 +18,10 @@ package im.vector.riotx.features.home
 
 import com.airbnb.mvrx.MvRxState
 import im.vector.matrix.android.api.session.sync.SyncState
+import im.vector.riotx.features.home.room.list.RoomListFragment
 
 data class HomeDetailViewState(
+        val displayMode: RoomListFragment.DisplayMode = RoomListFragment.DisplayMode.HOME,
         val notificationCountCatchup: Int = 0,
         val notificationHighlightCatchup: Boolean = false,
         val notificationCountPeople: Int = 0,